This invention relates generally to window assemblies and specifically to a composite window assembly used in an automotive vehicle.
Most automotive vehicles employ a window regulator or window lift mechanism for raising and lowering side windows within doors. Many of these window lift mechanisms are driven by fractional horsepower, dc electric motors actuated by a driver accessible switch. One window lift mechanism provides a perforated and flexible tape slidably mounted in a fixed channel track; this is shown in U.S. Pat. No. 4,222,202 entitled "Automotive Tape Drive Window Regulator" which issued to Pigeon on Sep. 16, 1980. It is also well known to provide a pair of crossed arms which act in a scissor-like manner to raise and lower side windows. This conventional construction is shown in U.S. Pat. No. 5,255,470 entitled "Vehicle Door Glass Regulator" which issued to Dupuy on Oct. 26, 1993. Another construction of a traditional manual crank window lift mechanism uses a threaded cable moving within a guide; such a construction is shown in U.S. Pat. No. 3,930,339 entitled "Window Regulator, Especially For Automobiles, With A Threaded Cable Moving In A Guide" which issued to Jander on Jan. 6, 1976. Furthermore, a traditional modular window lift mechanism employs a set of vertically oriented, C-shaped guide rails and a motor driven wire or cable. For instance, reference should be made to U.S. Pat. Nos. 5,351,443 entitled "Automotive Door With Window Pane Lifter Module" which issued to Kimura et al. on Oct. 4, 1994, and 5,226,259 entitled "Automotive Door With Power Window" which issued to Yamagata et al. on Jul. 13, 1993. Such conventional window lift mechanisms are made from relatively heavy metal stampings or castings.
Another conventional window lift mechanism raises and lowers a quarter window for use in a convertible vehicle. This mechanism employs a stamped metal guide plate, a stamped metal window mounting plate and a stamped metal regulator mounting plate. A pair of elongated C-shaped tracks, a pair of upstop retainers and a window tensioner are all welded or riveted to the guide plate. The window mounting plate has a pair of bent tabs upon which polymeric upstop isolator caps are mounted. Three threaded studs are welded or otherwise mounted upon window mounting plate around which polymeric spacers are disposed to prevent window scraping. A metal sector gear is pivotably mounted between the regulator mounting plate and the guide plate. A relatively flat, metallic extension arm, with an offset end, is welded or otherwise attached to the sector gear for movement therewith. The sector gear is driven by an electric motor which can provide approximately 90 inch-pounds of torque.
All of the aforementioned multi-piece, metal constructions are relatively heavy thereby requiring relatively large driving motors. Furthermore, these heavy units are relatively difficult to install, reduce vehicle miles per fuel gallon performance and are susceptible to increased gravitational force damage during usage on bumpy roads. The tracks employed in many of these systems are-also difficult and costly to manufacture within the requisite three-dimensional curved shapes. This tolerance miss-matching, in addition to the welding and riveting tolerance build-ups, create extreme friction, wear and binding within the system. This further increases the size of the driving motor and can cause excessive operational noise.
Additionally, many convertible roof assemblies are provided with quarter window retraction mechanisms. Such convertible top systems are shown in the following U.S. patents: U.S. Pat. No. 5,118,158 entitled "Convertible Top Linkage Assembly with Laterally Moving Rear Quarter Windows" which issued to Truskolaski on Jun. 2, 1992; U.S. Pat. No. 4,828,317 entitled "Convertible Top Frame with Quarter Windows" which issued to Muscat on May 9, 1989; U.S. Pat. No. 4,784,428 entitled "Apparatus and Method of a Convertible Top with Hard Glass with Bottom Sealing" which issued to Moy et al. on Nov. 15, 1988; U.S. Pat. No. 4,778,215 entitled "Flexible Roof for Motor Vehicles" which issued to Ramaciotti on Oct. 18, 1988;U.S. Pat. No. 3,536,354 entitled "Vehicle Bodies" which issued to Ingram on Oct. 27, 1970; and 2,267,471 entitled "Collapsible Top for Motor Vehicles" which issued to Keller on Dec. 23, 1941; all of which are incorporated by reference herewithin. Most of these units mechanically couple the window movement to retraction of the roof linkages.
In accordance with the present invention, the preferred embodiment of a composite window assembly for use in an automotive vehicle includes a composite guide plate. In another aspect of the present invention, the composite guide plate is molded from a polymeric material. In a further aspect of the present invention, the guide plate has a pair of auxiliary guide structures integrally extending proximate with edges thereof. In yet another aspect of the present invention, a pair of stop retaining bosses and a window tensioner are integrally molded as part of the composite guide plate. In still another aspect of the present invention, a T-shaped main guide structure is centrally provided on the composite guide plate. Another aspect of the present invention provides a molded polymeric composite sector gear with an integrated extension arm. Moreover, in still another aspect of the present invention, a molded composite window mounting plate with integral stops is provided. Another aspect of the present invention provides a guide, retention means and ball bearing construction. A method of manufacturing the present invention is also disclosed.
The composite window assembly of the present invention is advantageous over traditional constructions in that the present invention achieves lightweight and more accurately formed composite components. This is accomplished by molding various components from a polymeric material and by integrating multiple members into single units. Therefore, part tolerances are improved while lighter weight materials are employed thereby creating less part-to-part friction and weight; this also allows for use of a sign driving electrical motor. The polymeric material used is also inherently lubricous so as to further reduce part interfacing friction, window scraping and the need for messy lubricants. The present invention is further advantageous by reducing parts, reducing tooling costs, reducing piece costs, eliminating the need for painting, reducing part stress, improving part accuracy, and reducing operational noise. In fact, it has been found that the production tooling costs needed to produce the composite guide plates and composite window mounting plate are over four and one half times less than that of conventional tooling. Production piece cost is believed to be over four times less expensive than that of conventional metal parts. Moreover, the composite window assembly of the present invention allows for miniaturization of components and modularized assembly. Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.